Whirlpool Galaxy

astronomy

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June 24, 2026

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The Whirlpool Galaxy, also known as M51, is classified as an Sc galaxy. This type of galaxy is characterized by a small nucleus and open, well-defined spiral arms that extend outward. These arms are notable for containing numerous star clouds, associations, clusters, and emission nebulae, giving them a lumpy appearance.1

The Whirlpool Galaxy is a prime example of a spiral galaxy, a category defined by a bright nucleus surrounded by a disk and spiral structure. These galaxies can be normal spirals or barred spirals, with arms winding from the nucleus or from the ends of a central bar, respectively. The Whirlpool Galaxy's structure, with its prominent arms winding from a tiny nucleus, is a key feature used in its classification.1

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galaxy
Sc galaxies
…(1) galaxies, such as the Whirlpool Galaxy (M51), that have thin branched arms that wind outward from a tiny nucleus, usually extending out about 180° before branching into multiple segments, (2) systems with multiple arms that start tangent to a bright ring centred on the nucleus, (3) those with arms…
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…(1) galaxies, such as the Whirlpool Galaxy (M51), that have thin branched arms that wind outward from a tiny nucleus, usually extending out about 180° before branching into multiple segments, (2) systems with multiple arms that start tangent to a bright ring centred on the nucleus, (3) those with arms…
Read More